Example 6-9 from the red book written in LWJGL:
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.nio.FloatBuffer;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import org.lwjgl.BufferUtils;
import org.lwjgl.LWJGLException;
import org.lwjgl.input.Keyboard;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import org.lwjgl.util.glu.GLU;
import static org.lwjgl.opengl.GL11.*;
import static org.lwjgl.opengl.GL14.*;
import static org.lwjgl.opengl.GL15.*;
public class FogCoord {
private static final int WIDTH = 800, HEIGHT = 600;
private static final DisplayMode DISPLAY_MODE = new DisplayMode(WIDTH, HEIGHT);
private static final String WINDOW_TITLE = "Fog Coordinates Test";
private static final int FPS = 70; //frames per second
private boolean isRunning; //variable to tell if program is running or not
/* ------- Code added for Fog Coord --------*/
private float f1, f2, f3;
/* ------- End Code added for Fog Coord --------*/
/*---------Added for Controller purposes -----------*/
private JFrame frame;
private JPanel f1Panel, f2Panel, f3Panel, zoomPanel;
private JSlider f1Slider, f2Slider, f3Slider, zoomSlider;
private static final int MIN = -20;
private static final int MAX = 20;
private float zoom = 0.0f;
/*---------End - Added for Controller purposes -----------*/
public static void main(String[] args) {
FogCoord test = new FogCoord();
test.run();
}
/* -------- Constructor sets up GUI --------*/
public FogCoord() {
frame = new JFrame(WINDOW_TITLE + " Controller");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel pane = new JPanel();
pane.setPreferredSize(new Dimension(600,350));
f1Panel = new JPanel(new BorderLayout());
f1Panel.setBorder(BorderFactory.createTitledBorder("Vertex f1"));
f1Panel.setPreferredSize( new Dimension(150, 240));
f1Slider = new JSlider(JSlider.VERTICAL, MIN, MAX, 1);
f1Slider.setMajorTickSpacing(10);
f1Slider.setMinorTickSpacing(1);
f1Slider.setPaintTicks(true);
f1Slider.setPaintLabels(true);
f1Slider.addChangeListener(new ChangeListener() {
@Override
public void stateChanged(ChangeEvent e) {
JSlider source = (JSlider)e.getSource();
if (source.getValueIsAdjusting()) {
int f = source.getValue();
f1 = f;
}
}
});
f1Panel.add(f1Slider);
f2Panel = new JPanel();
f2Panel.setBorder(BorderFactory.createTitledBorder("Vertex f2"));
f2Panel.setPreferredSize( new Dimension(150, 240));
f2Slider = new JSlider(JSlider.VERTICAL, MIN, MAX, 5);
f2Slider.setMajorTickSpacing(10);
f2Slider.setMinorTickSpacing(1);
f2Slider.setPaintTicks(true);
f2Slider.setPaintLabels(true);
f2Slider.addChangeListener(new ChangeListener() {
@Override
public void stateChanged(ChangeEvent e) {
JSlider source = (JSlider)e.getSource();
if (source.getValueIsAdjusting()) {
int f = source.getValue();
f2 = f;
}
}
});
f2Panel.add(f2Slider);
f3Panel = new JPanel();
f3Panel.setBorder(BorderFactory.createTitledBorder("Vertex f3"));
f3Panel.setPreferredSize( new Dimension(150, 240));
f3Slider = new JSlider(JSlider.VERTICAL, MIN, MAX, 10);
f3Slider.setMajorTickSpacing(10);
f3Slider.setMinorTickSpacing(1);
f3Slider.setPaintTicks(true);
f3Slider.setPaintLabels(true);
f3Slider.addChangeListener(new ChangeListener() {
@Override
public void stateChanged(ChangeEvent e) {
JSlider source = (JSlider)e.getSource();
if (source.getValueIsAdjusting()) {
int f = source.getValue();
f3 = f;
}
}
});
f3Panel.add(f3Slider);
zoomPanel = new JPanel();
zoomPanel.setPreferredSize(new Dimension(550, 100));
zoomPanel.setBorder(BorderFactory.createTitledBorder("Other Options"));
zoomSlider = new JSlider(JSlider.HORIZONTAL, -100, 100, 0);
zoomSlider.setMajorTickSpacing(50);
zoomSlider.setMinorTickSpacing(25);
zoomSlider.setPaintTicks(true);
zoomSlider.setPaintLabels(true);
zoomSlider.addChangeListener(new ChangeListener() {
@Override
public void stateChanged(ChangeEvent e) {
JSlider source = (JSlider)e.getSource();
if (source.getValueIsAdjusting()) {
int f = source.getValue();
zoom = (float) (f/10.0);
}
}
});
zoomPanel.add(zoomSlider);
zoomPanel.add(new JLabel("Change from GL_FRAGMENT_DEPTH and GL_FOG_COORD by pressing 4 and 5 respectively."));
pane.add(f1Panel, BorderLayout.WEST);
pane.add(f2Panel, BorderLayout.CENTER);
pane.add(f3Panel, BorderLayout.EAST);
pane.add(zoomPanel, BorderLayout.SOUTH);
frame.setContentPane(pane);
frame.pack();
frame.setVisible(true);
}
private void run() {
try {
init();
while( isRunning ) {
getInput(); //read input
render(); //render graphics
Display.sync(FPS); //sync to fps
Display.update(); //update the view/screen
}
} catch (Exception e) {
e.printStackTrace();
System.exit(1);
}
}
private void render() {
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
glTranslatef(0.0f, 0.0f, zoom);
glColor3f(1.0f, 0.75f, 0.0f);
glBegin(GL_TRIANGLES); {
glFogCoordf(f1);
glVertex3f(2.0f, -2.0f, 0.0f);
glFogCoordf(f2);
glVertex3f(-2.0f, 0.0f, -5.0f);
glFogCoordf(f3);
glVertex3f(0.0f, 2.0f, -10.0f);
} glEnd();
}
private void getInput() {
if(Keyboard.isKeyDown(Keyboard.KEY_ESCAPE)) { // if user presses escape key
isRunning = false;
frame.dispose();
}
if( Display.isCloseRequested()) { // if user closes window
isRunning = false;
frame.dispose();
}
if(Keyboard.isKeyDown(Keyboard.KEY_4)){
glFogi(GL_FOG_COORD_SRC, GL_FRAGMENT_DEPTH);
}
if(Keyboard.isKeyDown(Keyboard.KEY_5)){
glFogi(GL_FOG_COORD_SRC, GL_FOG_COORD);
}
if(Keyboard.isKeyDown(Keyboard.KEY_1)){
f1 += 0.25f;
}
if(Keyboard.isKeyDown(Keyboard.KEY_2)){
f2 += 0.25f;
}
if(Keyboard.isKeyDown(Keyboard.KEY_3)){
f3 += 0.25f;
}
if(Keyboard.isKeyDown(Keyboard.KEY_8)){
f1 -= 0.25f;
}
if(Keyboard.isKeyDown(Keyboard.KEY_9)){
f2 -= 0.25f;
}
if(Keyboard.isKeyDown(Keyboard.KEY_0)){
f3 -= 0.25f;
}
if(Keyboard.isKeyDown(Keyboard.KEY_UP)){
glTranslatef(0f,0f,zoom-=0.25f);
}
if(Keyboard.isKeyDown(Keyboard.KEY_DOWN)){
glTranslatef(0f,0f,zoom+=0.25f);
}
}
private void init() {
createWindow();
initGL();
isRunning = true;
}
private void createWindow() {
try {
Display.setDisplayMode(DISPLAY_MODE);
Display.setTitle(WINDOW_TITLE);
Display.create();
} catch (LWJGLException e){
e.printStackTrace();
}
}
private void initGL() {
//glClearColor(0.5f, 0.5f, 0.5f, 0.0f); // sets background to grey
glClearDepth(1.0f); // clear depth buffer
glEnable(GL_DEPTH_TEST); // Enables depth testing
glDepthFunc(GL_LEQUAL); // sets the type of test to use for depth testing
glMatrixMode(GL_PROJECTION); // sets the matrix mode to project
float fovy = 45.0f;
float aspect = DISPLAY_MODE.getWidth() / (float)DISPLAY_MODE.getHeight();
float zNear = 0.1f;
float zFar = 100.0f;
GLU.gluPerspective(fovy, aspect, zNear, zFar);
glMatrixMode(GL_MODELVIEW);
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
/* ------- Code added for Fog Coord --------*/
FloatBuffer fogColor = BufferUtils.createFloatBuffer(4);
fogColor.put(0f).put(0.25f).put(0.25f).put(1.0f).flip();
f1 = 1.0f;
f2 = 5.0f;
f3 = 10.0f;
glEnable(GL_FOG); {
glFogi(GL_FOG_MODE, GL_EXP);
glFog(GL_FOG_COLOR, fogColor);
glFogf(GL_FOG_DENSITY, 0.25f);
glHint(GL_FOG_HINT, GL_DONT_CARE);
glFogi(GL_FOG_COORD_SRC, GL_FOG_COORD);
glClearColor(0.0f, 0.25f, 0.25f, 1.0f);
}
/* ------- End - Code added for Fog Coord --------*/
}
}
Edited by lethalwire, 18 December 2011 - 09:24 PM.
